Typhoid fever is caused by Salmonella typhi bacteria. Typhoid fever is rare in industrialized countries. However, it remains a serious health threat in the developing world, especially for children.

Typhoid fever spreads through contaminated food and water or through close contact with someone who's infected. Signs and symptoms usually include high fever, headache, abdominal pain, and either constipation or diarrhea.

When treated with antibiotics, most people with typhoid fever feel better within a few days, although a small percentage of them may die of complications.

Vaccines against typhoid fever are available, but they're only partially effective. Vaccines usually are reserved for those who may be exposed to the disease or are traveling to areas where typhoid fever is common.

Although children with typhoid fever sometimes become sick suddenly, signs and symptoms are more likely to develop gradually — often appearing one to three weeks after exposure to the disease.

1st week of illness

Once signs and symptoms do appear, you're likely to experience:

Fever, that starts low and increases daily, often to as high as 103 or 104 F (39.4 or 40 C)

Headache

Weakness and fatigue

Dry cough

Loss of appetite

Abdominal pain

Diarrhea or constipation

Rash

2nd week of illness

If you don't receive treatment for typhoid fever, you may enter a second stage during which you become very ill and experience:

Continuing high fever

Either diarrhea or severe constipation

Considerable weight loss

Extremely distended abdomen

3rd week of illness

By the third week, you may:

Become delirious

Lie motionless and exhausted with your eyes half-closed in what's known as the typhoid state

Life-threatening complications often develop at this time.

4th week of illness

Improvement may come slowly during the fourth week. Your fever is likely to decrease gradually until your temperature returns to normal in another week to 10 days. But signs and symptoms can return up to two weeks after your fever has subsided.

When to see a doctor

See a doctor immediately if you suspect you have typhoid fever. If you become ill while traveling in a foreign country, call the U.S. Consulate for a list of doctors. Better yet, find out in advance about medical care in the areas you'll visit, and carry a list of the names, addresses and phone numbers of recommended doctors.

If you develop signs and symptoms after you return home, consider consulting a doctor who focuses on international travel medicine or infectious diseases. A specialist may be able to recognize and treat your illness more quickly than can a doctor who isn't trained in these areas.

Typhoid fever is caused by a virulent bacterium called Salmonella typhi. Although they're related, S. typhi and the bacterium responsible for salmonellosis, another serious intestinal infection, aren't the same.

Fecal-oral transmission route

The bacteria that cause typhoid fever spread through contaminated food or water and occasionally through direct contact with someone who is infected. In developing nations, where typhoid is endemic, most cases result from contaminated drinking water and poor sanitation. The majority of people in industrialized countries pick up the typhoid bacteria while traveling and spread it to others through the fecal-oral route.

This means that S. typhi is passed in the feces and sometimes in the urine of infected people. You can contract the infection if you eat food handled by someone with typhoid fever who hasn't washed carefully after using the toilet. You can also become infected by drinking water contaminated with the bacteria.

Typhoid carriers

Even after treatment with antibiotics, a small number of people who recover from typhoid fever continue to harbor the bacteria in their intestinal tracts or gallbladders, often for years. These people, called chronic carriers, shed the bacteria in their feces and are capable of infecting others, although they no longer have signs or symptoms of the disease themselves.

Typhoid fever remains a serious worldwide threat — especially in the developing world — affecting an estimated 22 million people each year, according to the Centers for Disease Control and Prevention. The disease is endemic in India, Southeast Asia, Africa, South America and many other areas.

Worldwide, children are at greatest risk of getting the disease, although they generally have milder symptoms than adults do.

If you live in a country where typhoid fever is rare, you're at increased risk if you:

Work in or travel to areas where typhoid fever is endemic

Work as a clinical microbiologist handling Salmonella typhi bacteria

Have close contact with someone who is infected or has recently been infected with typhoid fever

Have an immune system weakened by medications such as corticosteroids or diseases such as HIV/AIDS

Drink water contaminated by sewage that contains S. typhi

Intestinal bleeding or holes

The most serious complication of typhoid fever — intestinal bleeding or holes (perforations) — may develop in the third week of illness. About 5 percent of people with typhoid fever experience this complication.

Intestinal bleeding is often marked by a sudden drop in blood pressure and shock, followed by the appearance of blood in your stool.

A perforated intestine occurs when your small intestine or large bowel develops a hole, causing intestinal contents to leak into your abdominal cavity and triggering signs and symptoms such as severe abdominal pain, nausea, vomiting and bloodstream infection (sepsis). This life-threatening emergency requires immediate medical care.

Other, less common complications

Other possible complications include:

Inflammation of the heart muscle (myocarditis)

Inflammation of the lining of the heart and valves (endocarditis)

Pneumonia

Inflammation of the pancreas (pancreatitis)

Inflammation of the gallbladder (cholecystitis)

Kidney or bladder infections

Infection and inflammation of the membranes and fluid surrounding your brain and spinal cord (meningitis)

Psychiatric problems such as delirium, hallucinations and paranoid psychosis

With prompt treatment, nearly all people in industrialized nations recover from typhoid. Without treatment, some people may not survive complications of the disease.

Call your doctor if you've recently returned from travel abroad and develop mild symptoms similar to those that occur with typhoid fever. If your symptoms are severe, go to an emergency room or call 911 or your local emergency number.

Here's some information to help you get ready and know what to expect from your doctor.

Information to gather in advance

Pre-appointment restrictions. At the time you make your appointment, ask if there are restrictions you need to follow in the time leading up to your visit. Your doctor will not be able to confirm typhoid fever without a blood test, and may recommend taking steps to reduce the risk of passing a possible contagious illness to others.

Symptom history. Write down any symptoms you''re experiencing and for how long.

Recent exposure to possible sources of infection. Be prepared to describe international trips in detail, including the countries you visited and the dates you traveled.

Medical history. Make a list of your key medical information, including other conditions for which you're being treated and any medications, vitamins or supplements you're taking. Your doctor will also need to know your vaccination history.

Questions to ask your doctor. Write down your questions in advance so that you can make the most of your time with your doctor.

For typhoid fever, possible questions to ask your doctor include:

What are the possible causes for my symptoms?

What kinds of tests do I need?

Are treatments available to help me recover?

How long do you expect a full recovery will take?

When can I return to work or school?

Am I at risk of any long-term complications from typhoid fever?

Don't hesitate to ask any other related questions you have.

What to expect from your doctor

Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to talk about in-depth. Your doctor may ask:

What are your symptoms?

When did you begin experiencing symptoms?

Have your symptoms gotten better or worse?

Did your symptoms briefly get better and then come back?

Have you recently traveled abroad? Where?

Did you update your vaccinations before traveling?

Are you being treated for any other medical conditions?

Are you currently taking any medications?

Medical and travel history

Your doctor is likely to suspect typhoid fever based on your symptoms and your medical and travel history. But the diagnosis is usually confirmed by identifying S. typhi in a culture of your blood or other body fluid or tissue.

Body fluid or tissue culture

For the culture, a small sample of your blood, stool, urine or bone marrow is placed on a special medium that encourages the growth of bacteria. In 48 to 72 hours, the culture is checked under a microscope for the presence of typhoid bacteria. A bone marrow culture often is the most sensitive test for S. typhi.

Although performing a culture test is the mainstay for diagnosis, in some instances other testing may be used to confirm a suspected typhoid infection, such as a test to detect antibodies to typhoid bacteria in your blood or a test that checks for typhoid DNA in your blood.

Antibiotic therapy is the only effective treatment for typhoid fever.

Commonly prescribed antibiotics

Ciprofloxacin (Cipro). In the United States, doctors often prescribe this for nonpregnant adults.

Ceftriaxone (Rocephin). This injectable antibiotic is an alternative for women who are pregnant and for children who may not be candidates for ciprofloxacin.

These drugs can cause side effects, and long-term use can lead to the development of antibiotic-resistant strains of bacteria.

Problems with antibiotic resistance

In the past, the drug of choice was chloramphenicol. Doctors no longer commonly use it, however, because of side effects, a high rate of health deterioration after a period of improvement (relapse), and widespread bacterial resistance.

In fact, the existence of antibiotic-resistant bacteria is a growing problem in the treatment of typhoid, especially in the developing world. In recent years, S. typhi also has proved resistant to trimethoprim-sulfamethoxazole and ampicillin.

Supportive therapy

Other treatment steps aimed at managing symptoms include:

Drinking fluids. This helps prevent the dehydration that results from a prolonged fever and diarrhea. If you're severely dehydrated, you may need to receive fluids through a vein in your arm (intravenously).

Eating a healthy diet. Nonbulky, high-calorie meals can help replace the nutrients you lose when you're sick.

In many developing nations, the public health goals that can help prevent and control typhoid — safe drinking water, improved sanitation and adequate medical care — may be difficult to achieve. For that reason, some experts believe that vaccinating high-risk populations is the best way to control typhoid fever.

The Centers for Disease Control and Prevention recommends being vaccinated if you''re traveling to areas where the risk of getting typhoid fever is high.

Vaccines

Two vaccines are available.

One is injected in a single dose about two weeks before exposure.

One is given orally in four capsules, with one capsule to be taken every other day.

Because the vaccine won't provide complete protection, follow these guidelines when traveling to high-risk areas as well:

Wash your hands. Frequent hand-washing is the best way to control infection. Wash your hands thoroughly with hot, soapy water, especially before eating or preparing food and after using the toilet. Carry an alcohol-based hand sanitizer for times when water isn't available.

Avoid drinking untreated water. Contaminated drinking water is a particular problem in areas where typhoid is endemic. For that reason, drink only bottled water or canned or bottled carbonated beverages, wine and beer. Carbonated bottled water is safer than uncarbonated bottled water is. Wipe the outside of all bottles and cans before you open them. Ask for drinks without ice. Use bottled water to brush your teeth, and try not to swallow water in the shower.

Avoid raw fruits and vegetables. Because raw produce may have been washed in unsafe water, avoid fruits and vegetables that you can't peel, especially lettuce. To be absolutely safe, you may want to avoid raw foods entirely.

Choose hot foods. Avoid food that's stored or served at room temperature. Steaming hot foods are best. And although there's no guarantee that meals served at the finest restaurants are safe, it's best to avoid food from street vendors — it's more likely to be contaminated.

Prevent infecting others

If you're recovering from typhoid, these measures can help keep others safe:

Wash your hands often. This is the single most important thing you can do to keep from spreading the infection to others. Use plenty of hot, soapy water and scrub thoroughly for at least 30 seconds, especially before eating and after using the toilet.

Clean household items daily. Clean toilets, door handles, telephone receivers and water taps at least once a day with a household cleaner and paper towels or disposable cloths.

Avoid handling food. Avoid preparing food for others until your doctor says you're no longer contagious. If you work in the food service industry or a health care facility, you won't be allowed to return to work until tests show that you're no longer shedding typhoid bacteria.

Keep personal items separate. Set aside towels, bed linen and utensils for your own use and wash them frequently in hot, soapy water. Heavily soiled items can be soaked first in disinfectant.

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